Publication detail

Porous‐Alumina‐Assisted Growth of Nanostructured Anodic Films on Ti−Nb Alloys

BENDOVÁ, M. KOLÁŘ, J. GISPERT-GUIRADO, F. MOZALEV, A.

Original Title

Porous‐Alumina‐Assisted Growth of Nanostructured Anodic Films on Ti−Nb Alloys

Type

journal article in Web of Science

Language

English

Original Abstract

Porous‐anodic‐alumina (PAA)‐assisted anodizing is employed, for the first time, for growing arrays of oxide nanocolumns on Ti−Nb alloy films with up to 58 at% Nb. Beyond about 24 at% Nb in the alloy, the system allows for high formation potentials of 250–420 V, giving columns that are 500–700 nm long, which are 100 % stable during the PAA etch. The stability worsens when lowering the Nb content in the alloy, owing to contamination of the column roots by alumina, which arises from the amorphous‐to‐crystalline transition of the anodic oxide, oxygen evolution, formation of O2‐filled nanobubbles within the roots, and development of bigger voids. The voids force the roots to regrow and spread laterally along with anodizing the surrounding Al residues, which increases alumina content in the titania‐based nanoroots. The incorporation of sufficient amounts of Nb2O5 in the anodic TiO2 hinders oxide crystallization and lowers alumina content in the roots, which stabilizes the columns. The two oxides are distributed uniformly along the columns, indicating comparable migration rates of Ti4+ and Nb5+ ions in the mixed anodic oxide. This uniform distribution, combined with possibly mixing the oxides at atomic level, is expected to narrow the band gap of the material, which is of vast importance for solar energy conversion applications.

Keywords

Anodizing, nanostructures, porous anodic alumina, Ti@Nb alloys, thin films

Authors

BENDOVÁ, M.; KOLÁŘ, J.; GISPERT-GUIRADO, F.; MOZALEV, A.

Released

1. 10. 2018

ISBN

2196-0216

Periodical

ChemElectroChem

Year of study

5

Number

19

State

Federal Republic of Germany

Pages from

2825

Pages to

2835

Pages count

11

URL

https://onlinelibrary.wiley.com/doi/abs/10.1002/celc.201800785

BibTex

@article{BUT150769,
  author="Mária {Bendová} and Jakub {Kolář} and Francesc {Gispert-Guirado} and Alexander {Mozalev}",
  title="Porous‐Alumina‐Assisted Growth of Nanostructured Anodic Films on Ti−Nb Alloys",
  journal="ChemElectroChem",
  year="2018",
  volume="5",
  number="19",
  pages="2825--2835",
  doi="10.1002/celc.201800785",
  issn="2196-0216",
  url="https://onlinelibrary.wiley.com/doi/abs/10.1002/celc.201800785"
}